Well, that's not exactly fair. Avatar TLA, Batman TAS, and Gargoyles were also all made for children, but took themselves and their audience seriously. Just because it's made for kids doesn't mean you have to do it poorly or crappily.

Absolutely right. In fact, the attitude that anything meant for children can be handled shoddily, that quality should be reserved only for adults, is quite a horrifying notion if you think about it. Surely we owe it to our children to strive for the highest quality in everything we do for them.

Gotham Central wrote:

Communications would not diminish the need for a HQ. The other reason for having a meeting place is to promote the idea of "the team" as a single unit. That means all the members need t spend time together, train together, and share common tasks. This gives each member of the group an idea of what the other members are capable of doing out in the field. Groups inherently work better when they spend time together.

Headquarters also serves as a means of equalizing the resources of the team. Historically, through the headquarters, the rich members end up subsidizing the activities of the other members. Less affluent members or members not from Earth will frequently live in the HQ full time

There's also the matter of operational security. Communications can be intercepted. Although that rationale works best for a secret HQ, or an inaccessible one like the Watchtower.